BRPI1105455A2 - spinal implant for stabilization and stiffening of vertebral bodies of a spine - Google Patents

Abstract

Spinal Implant for Stabilization and Stiffening of Vertebral Bodies of a Spinal Column - The invention relates to a spinal implant (1) for stabilization and stiffening of vertebral bodies of a spine comprising first bony screws (6) , which can be screwed into a vertebral body, and second bone screws (2), which can also be screwed into a vertebral body. First connecting elements (8), which are rigid, can be attached to the first receiving means (7) of the first bone screws (6). Second connecting elements (5), which are elastic, may be attached to the second receiving means (4) of the second bone screws (2). By coupling means (9) a first connection element (8) can in each case be connected to a second connection element (5). For this purpose, the coupling means (9) with a first region (10) may be detachably attached to a second bone screw (2), in which a terminal region (11) of a second coupling member is retained. connection (5). In addition, the coupling means (9) with a second region (12) opposite the first region (10) may be fixed to an end region (13) of a first connection element (8). By this configuration, a rigid spinal implant region can be simply disengaged from an elastic, stabilizing spinal implant.

Description

Report of the Invention Patent for "VERTEBRAL SPINE IMPLANTS FOR STABILIZATION AND STRENGTHENING OF VERTEBRAL BODIES".

The present invention relates to a spinal implant for stabilization and stiffening of vertebral bodies of a vertebral column, comprising first bony screws consisting of a screw-on part which can be screwed into a vertebral body, and first reception means; second bone screws, consisting of a screw-on part, which may be screwed into a vertebral body, and second receiving means; first connecting elements, which are rigid and may be inserted into the first receiving means of the first bone screws and may be attached thereto; second connecting elements, which are elastic and may be inserted into the second receiving means of the second bone screws and may be attached thereto; and coupling means, whereby a first connecting element and a second connecting element may in each case be connected to one another.

These spinal implants are known in various configurations. With these spinal implants it can be obtained that in the spine a rigid stabilization of the vertebral bodies is made possible regionally, while in other regions the vertebral bodies are sustained and stabilized by the elastic configuration of the system, without occurring a stiffening. In the region of rigid stabilization of vertebral bodies, it is desirable to achieve bone growth of the affected and stabilized vertebral bodies; With elastic stabilization, no stiffening of the vertebral bodies should occur.

Such a spinal implant for stabilization and stiffening of vertebral bodies in a spine is known, for example, from EP-A 1961392. If, after a certain period of time, intergrowth and osse-

Verification of vertebral bodies relative to each other, which have been strengthened or stiffened by the spinal implant, has progressed to such a degree that inherent stability exists, the spinal implant stiffening regions are no longer needed; therefore, they become quite superfluous and may interfere. Therefore, it would be reasonable that, after the respective intergrowth process, these spinal implant stiffening regions could be completely decoupled from the elastic stabilization region or, if necessary, even removed while the spinal implant regions which serve for the stabilization of vertebral bodies must be maintained in order to be able to continue to have this supportive and stabilizing effect. This means that the stiffening region and the stabilization and support region of the spine implant can be simply decoupled from each other, which is not possible with known spinal implants.

The object of the present invention is therefore to configure a spinal implant for stabilization and stiffening of vertebral bodies of a spine such that the stabilization region, which has an elastic connecting element, and the Rigid region, with a rigid connecting element, are connected to each other such that they can be decoupled from each other in the simplest manner.

This object is obtained according to the invention by the fact that the coupling means, with a first region, can be detachably fixed to a second bone screw, and in the second bone screw a terminal region of a second bone is retained. second connector element, and coupling means with a second region opposite the first region may be connected to an end region of a first connector element.

Through this solution, the rigid region of the spinal implant is capable of being easily uncoupled from the stabilization and elastic region. The connection of the second bone screw to the terminal region of the second connection element remains during surgery. Therefore, nothing changes regarding the stabilizing capacity of this elastic region of the spinal implant.

Preferably, the first region of the coupling means is provided with a tensioning element, which is guided insertable into the second receiving means and by means of tensioning means, which may be mounted on the second receiving means, may be tensioned against the second element. connection cable inserted into the second receiving medium. The coupling means can thus be simply connected to the second bone screw.

Preferably, the second receiving means are U-shaped and are composed of two arms, between which the support surface for the second connecting element is arranged and on which two arms of the tensioning means, consisting of In a locking element provided with a first tensioning screw, they can be arranged and locked with it, which simplifies the procedure during surgical intervention.

Preferably, the tensioning element is provided with guide ribs, which, together with guide surfaces provided on the arms, form the guides, which results in a simple construction.

Another advantageous embodiment of the invention is that the second region of the coupling means is configured as another tensioning means to which an end region of a first connection element can be attached. During the respective surgical intervention, this possibility of additional separation facilitates both the insertion and uncoupling of this region of the spinal implant.

An especially simple construction for this other tensioning means is obtained by the fact that this other tensioning means has a U-shaped receiving portion for the first connecting element and a threaded portion opposite the U-shaped receiving portion for receive a second turnbuckle.

Improved tightening of the first connecting element with the other tensioning means can be achieved by the fact that a tightening element is inserted between the second tensioning screw and the first connecting element.

Another advantageous embodiment of the invention is that the tensioning link and the other tensioning means, which form the coupling means, are detachably connected to each other, which facilitates manipulation during the respective surgical intervention.

Preferably, the tensioning member has at least one nose-like protrusion that protrudes into the other tensioning means, whereby a very simple construction for such a connection is obtained.

Another advantageous embodiment of the invention is that the nose-shaped protrusion is provided with a threaded hole into which another tensioning screw can be screwed in, with the nose-like protrusion protruding between the second tensioning screw and the first connecting element of the other tensioning means. The position of the nose-like protrusion with respect to the connecting element can thus be adjusted whereby, for example, first connecting elements of different diameters can be used. Another advantageous embodiment of the invention is that

that the second connecting members have a surface structure consisting of ribs and ribs extending substantially transverse to the longitudinal axis, and by the fact that the second receiving means and the surface of the tensioning means faces the second connecting member. ribs are provided with ribs and strictures corresponding to the ribs and ribs of the second connecting element. A positive socket connection can thus be optimally achieved between the second connecting element and the second receiving means of the second bone screw.

Embodiments of the present invention are explained in more detail below, by way of example, with reference to the accompanying drawings.

Figure 1 shows in a three-dimensional representation a first embodiment of a part of a spinal implant according to the invention;

Figure 2 shows in a three-dimensional representation a second bone screw with tensioning means of the spinal implant according to the invention;

Figure 3 shows a cross-sectional view through the tensioning means according to figure 2;

Figure 4 shows in a three-dimensional representation the spinal implant according to figure 1, with coupling means illustrated with individual components;

Figure 5 shows a sectional view through the other tensioning means

the spinal implant according to figure 1;

Figure 6 shows a top view of the three dimensionally represented tensioning member of the spinal implant according to Figure 1;

Figure 7 shows a bottom view of the tensioning element represented by

sitting three-dimensionally according to figure 6;

Figure 8 shows in a three-dimensional representation a second embodiment of a part of a spinal implant according to the invention, with coupling means shown with individual components;

Figure 9 shows a cross-sectional view through the tensioning means of the spinal implant according to Figure 8;

Figure 10 shows a top view of the three-dimensional tensioning member of the spinal implant according to Figure 8;

Figure 11 shows a bottom view of the tensioning element represented three-dimensionally according to Figure 10;

Figure 12 shows in a three-dimensional representation a third embodiment of a part of a spinal implant according to the invention, with coupling means shown with individual components;

Figure 13 shows a cross-sectional view through the tensioning means of the spinal implant according to Figure 12;

Figure 14 shows a top view of the three-dimensional tensioning member of the spinal implant according to Figure 12;

Figure 15 shows a bottom view of the tensioning element represented three-dimensionally according to figure 14.

As can be seen from Figure 1, a part of a spinal implant 1 according to the invention for stabilizing and stiffening the vertebral bodies of a spine is comprised of second bone screws 2 which in each In this case, they comprise a screwing part 3 provided with a thread and second receiving means

4. In a known manner, such a second bone screw 2, with the screwable part 3, may be screwed into a vertebral body of a vertebral column. Firmly inserted and retained in the second receiver means 4

a second connecting element 5. This second connecting element 5 is rod-shaped and is made of an elastic material, for example a biocompatible synthetic material based on polyurethane.

The spinal implant 1 according to the invention further comprises first bony screws 6, which also have, in a known manner, a screwable part, which is not shown in the figures, but which corresponds to the screwable part 3 of the second one. bone screw 2 and is correspondingly bolted to the desired vertebral body of the spine. These first bony screws 6 are provided with first receiving means 7 into which a first connection element 8, which is shaped like a rod, can be inserted and fixed. This first connecting element 8 is rigid and is made of a metallic material, for example a titanium alloy.

The respective first connection element 8 may in each case be connected to a second connection element 5 adjacent thereto by means of coupling means 9. These coupling means 9 are detachably retained on a second screw bone 2 by means of a first region 10, which bone screw in which an end region 11 of the second connecting element is also retained.

5. The second region 12, opposite the first region 10, of coupling means 9 may be connected to a terminal region 13 of a first element.

8, which will be described later in detail.

This spinal implant 1 is adaptable in virtually any way desired to the spine to be stabilized. This spinal implant may consist of first rigid connection elements 8 and second elastic connection elements 5, which cooperate with the respective first and second bone screws 6 or 2. The respective connection elements 8 and 5 may be dimensioned to the desired length and, by corresponding combinations, the spine may be resiliently stabilized in the desired regions and other desired regions, may be strengthened or stiffened, and the corresponding bone screw is screwed in in each case. in the intended vertebral body.

The structure of the second bone screws 2 is shown in Figures 2 and 3. The second receiving means 4, connected to the screwable part 3, are provided with a U-shaped recess 14, which is formed by the inner surfaces 15, Two arms 16, 18. The two inner surfaces 15 and 16 of these two arms 17 and 18 are connected to each other by a bearing surface 19, the inner surfaces 15 and 16 and the bearing surface 19 being adapted to the the shape of the second connector 5 to be inserted into these U-shaped recesses 14, in which grooves and slots 41, 42 are provided, in which corresponding slots 43 and grooves provided in the second connector 5 (figure 1) engage in the inserted state, and thereby a positive snap connection is formed.

The two lateral regions of the respective arms 17 and 18 are provided in each case with a guide surface 20, 21. In the upper region on the outside of the two arms 17 and 18 there is provided in each case a slot 22 which extends transversely to these arms. The bottom of the groove and the surfaces bordering the groove 22 have a circular configuration.

The U-shaped recess of the second receiving means 4 of the second bone screw 2 is closed by tensioning means 23. These tensioning means 23 are comprised of a tensioning element 24, a locking element 25 and a first tensioning screw 26. The tensioning element It may be inserted between the two arms 17 and 18. For this purpose, this tensioning member 24 is provided with two opposite guide ribs 27 and 28 which together with the guide surfaces 20 and 21 of the two. arms 17 and 18 form the guide. The surface 29 of the tensioning member 24 facing the bearing surface 19 also has a shape adapted to the shape of the second connecting member 5 (Figure 1).

The locking element 25 is in the shape of an arc, and in the two opposite end regions there is in each case a rim 30. A protrusion 31 is provided on each of these 30 rims 30. that are directed towards each other. In addition, the locking element 25 is provided with a hole 32, which is provided with a thread 33. The first tensioning screw 26 can be screwed into the thread 33 of that hole 32, which tensioning screw is provided with a hexagonal recess. 34. With such tensioning means 23, the U-shaped recess 14 can be closed on the second receiving means 4 of the second bone screw; In this way, the second connecting element disposed on this U-shaped socket is locked in position.

As can be seen from figure 3, the tensioning means 23 may be mounted in a unit. The first tensioning screw 26 is provided with a threaded portion 35, to which is added a bolt part with nut 36. Between the threaded part 35 and the bolt part with nut 36 is formed a bearing surface 37. The bolt part with nut 36 protrudes into a central bore 38 which is made in the tensioning member 24. The end region of the nut bolt 36 spaced apart from the threaded part 35 is provided with a thickening 39 which can be obtained , for example, by wrinkling the end region of this bolt piece with nut 36, which can be performed after inserting the first turnbuckle 26 into the turnbuckle 24. The first turnbuckle 26 and the clamping element 24 are therefore rotatably connected to each other around the nut bolt 36. The first clamping screw 26 with the clamping element 24 attached thereto can then be screwed into the clamping element. lock 25, whereby the tensioning means 24 is formed as a unit. For placement of the tensioning means 23 on the second bone screw 2, the locking element 25 is aligned transversely with respect to the tensioning element 24. The tensioning means 23 can then be moved into the U-shaped recess 14 of the second bone screw 2. The guide ribs 27 and 28 of the tensioning element are guided by the guide surfaces 20 and 21 of the two arms 17 and 18. The locking element 25 can then be rotated about the axis of the first tensioning screw 26 on the guide rib 28, until the locking member 25 is located in the locked position, as can be seen from figure 1. The first turnbuckle 26 can then be tightened and the second connecting member 5 locked in position. in the second bone screw 2.

As can be seen from Fig. 1, the first receiving means 7 of the first bone screw 6 consist in each case of two arms 45 and 46, forming a U-shape into which the first connecting element can be placed. 8. A thread 47 is provided on the inner side of the arms 45 and 46. This thread 47 can also be screwed into a tensioning screw 48, with which the first connecting element 8 can be locked in position on the first bone screw 6. Of course, it would also be conceivable to configure the first receiving means 7 of the first bone screw 6 differently, in a manner known, for example, such that the first connecting element 8 can be locked in position in the first receiving means 7.

The structure of the coupling means 9 used in this first embodiment is shown in figures 4 to 7. Figure 4 shows again the spinal implant 1 according to figure 1, with first bony screws 6 and first receiving means 7, in which the first connecting element 8 is retained, as well as second bone screws 2, with second receiving means 4, in which the second connecting element 5 is retained.

The first region 10 of the coupling means 9 is formed by a tensioning member 24, as shown in Figures 2 and 3. This tensioning member 24 is part of the tensioning means 23, with which a second bone screw 2 can be closed. The tensioning member 24 is provided here with a nose-shaped protrusion 49 extending longitudinally beyond the end region 11 of the second connection element 5 and extending parallel to the end region 13 of the first connection element 8. This tensioning member 24 with the nose-like protrusion 49 can be seen in detail in figures 6 and 7. In order to make the locking element 25 shown in figure 2 rotatable with respect to that element tensioning member 24, the tensioning element 24 is provided with a slotted recess 50 which extends circularly in the region of the protrusion 48 in the manner of nose.

As can also be seen from Figure 4, the second region 12 of the coupling means 9 is configured as another tensioning means 51 having a U-shaped receiving portion 52 for the first connecting element 8. The second portion U-shaped receiver 52 is closed by a lid 53, which is provided with a through hole 54. A clamping member 55 is insertable into the other tensioning means 51, through that through hole 54, which is rotatable in the other. tensioning means 51 and is provided with a slot 56. The other tensioning means 51 is pushed over the first connecting element 8, and the clamping element 55 is inserted into the other tensioning means 51 through hole 54, and is rotated so that by pushing that other tensioning means 51, with the clamping member 55 inserted, towards the nose-like protrusion 49 of the tensioning member 24, that nose-shaped protrusion 49 moves in the slot 56. second turnbuckle 57 may then be screwed into the other turnbuckle 51 to for which purpose the other tensioning means 51 is provided with a corresponding internal thread 58 in the region of the through hole 54.

In Fig. 5 the other tensioning means 51 is shown in the state in which the first connecting element 8 and the nose-like protrusion 49 are attached to this other tensioning means 51. It can be seen here that the lower surface of the clamping element 55 is compressed in the first connection member 8, which rests at the bottom of the U-shaped receiving portion 52. The nose-shaped protrusion 49 protrudes into the slot 56 (Fig. 4) of the clamping member 55 wherein the nose-like projection is clamped between the transverse pieces 59 and 60 of the clamping member 55, which transverse pieces may move elastically towards each other. By means of the second tensioning screw 57, which is screwed and tightened on the internal thread 58 of the other tensioning means 51, the necessary tightening forces are applied to retain the first connecting element 8 and the protrusion 49 in the nose manner on the other tensioning means. 51

The great advantage of the spinal implant shown here is that after the growth of the vertebral bodies fixed by the first rigid connecting element, this rigid reinforcement can be completely decoupled from the region, which is stabilizing for the vertebral bodies by of the second flexible connection element 5. This stabilized flexible region must, however, continue to fulfill the stabilizing function, to decouple the rigid part of the elastic part of the spinal implant, the second tensioning screw 57 of the other tensioning means 51 may be loosened, the other tensioning means 51 may be pushed together with the clamping member 55 along the first connecting element 8 away from the second bone screw 2, and the clamping member 55 may be removed from the other tensioning means 51. Then the tensioning means 23 The second bone screw 2, which receives the terminal region 11, can be detached. The tensioning member 24 can then be lifted off and from the second bone screw 2 axially thereto. By positively connecting the second connection element 5 to the second bone screw 2, this connection remains stable; a tensioning means 23, whose tensioning element 24 is of "normal" configuration, without nose-like protrusion 49, can then be placed on the bone screw 2. Thus, in this way, the rigid region of the spinal implant 1, then arresting given its function, it can be completely decoupled from the elastic region. A gap results between the first connecting element 8 and the second connecting element 5, so that no force can yet be transmitted from one connecting element to the other connecting element. It is also conceivable that after the growth of the vertebral bodies fixed by means of the first rigid connection element 8, the first rigid connection element 8 and, if necessary, the first bony screws are removed from the patient's body, which consequently, it may be detached from the coupling means 9 and, without negative effects on stabilization, the elastic region of the spinal implant; the elastic region of the spinal implant remains unchanged in the body.

The second embodiment of the spinal implant 1 according to the invention, as shown in Figures 8-11, differs from the first example of an initially described embodiment of a spinal implant only in that that coupling means 9 are configured differently. . As can be understood from Figures 8, 10 and 11, the nose-shaped protrusion 49, which is provided on the tensioning member 24, consists of two parallel extending transverse pieces 59 and 60. Clamping member 55 is comprised of a base plate 61 and a cylindrical portion 62. That clamping member 55 may once again be inserted into the other tensioning means 51. The two transverse pieces 59 and 60 terminate again in the other means. With the second tensioning screw 57, the first connecting element 8 can be connected to the tensioning element 24. Figure 9 shows that in assembled state, the first connecting element 8 is placed in the U-shaped receiving part and is sustained on the same. The base plate 61 of the clamping elements 55 is compressed against the first connecting element 8 by the fact that the two cross pieces 59 and 60 of the clamping element 55 are compressed against that base plate 61. by means of the second tensioning screw 57. Optimum attachment of the first connecting element 8 by means of the tensioning element 24 is thus also achieved here. Uncoupling of the rigid region of the spine implant from the elastic region of the spine implant is also possible here as simply as previously described.

The third embodiment example of a spinal implant 1 according to the invention is shown in figures 12-15. This embodiment example differs once again through a coupling means 9 configured differently from the two previously described embodiment examples. As seen from Figures 12, 14 and 15, the tensioning element 24, which is insertable into the second bone screw 2, is again provided with a nose-like protrusion 49. Compared to the nose-shaped protrusion 49 according to the first embodiment example, it is more broadly configured. A hole 63, which is provided with an internal thread, is produced in this protrusion 49 at the nose end. In this threaded hole 63 another tightening screw 64 can be screwed.

In the assembled state of this coupling means 9, as can be seen from Figure 13, the first connecting element 8 is located in the U-shaped receiving portion 52 of the other tensioning means 51. The nose-shaped protrusion 49 protrudes from the nose. into the U-shaped receiving portion 52 of the other tensioning means 51. The other tensioning screw screwed into the threaded hole 63 of the nose 49 compresses the first connecting element 8. The second tensioning screw 57 in turn instead, it compresses the protrusion 49 in the manner of a nose. The first connecting element 8 and the nose-shaped protrusion 49 are thereby tightly fixed to the other tensioning means 51. The position of the height of the nose-shaped protrusion 49 with respect to the first connecting element 8 can be adjusted by corresponding tightening of the other tensioning screw 64, whereby adaptations of the position of the first connecting element 8 with respect to the adjacent second bone screw 2 and thus to the second adjustment element can be optimally performed. connection 5.

With this configuration of the coupling medium 9, the rigid region of the spine implant can also be decoupled from the simplest way of the elastic stabilization region of the spine implant, as previously described, by the fact that the second turnbuckle 57 and the other turnbuckle 64 are unscrewed and removed.

With this spinal implant according to the invention, as already mentioned, the advantage is obtained that after ossification of the vertebral bodies, which is obtained through a rigid region of a spinal implant , this rigid region can be simply decoupled from the elastic stabilization region of this spinal implant. This also makes it possible, when necessary, for simple removal of the rigid spinal implant region of the body, without negatively affecting the stabilizing elastic region of the spinal implant.

Claims (12)

1. Spinal implant for stabilization and stiffening of vertebral bodies of a vertebral column, comprising: first bony screws (6) consisting of a screw-on part (3) which can be screwed into a vertebral body; and first receptor means (7); second bone screws (2), consisting of a screw-on part (3), which may be screwed into a vertebral body, and second receptor means (4); first connecting elements (8), which are rigid and may be inserted into the first receiving means (7) of the first bone screws (6) and may be attached thereto; second connecting elements (5) which are elastic and may be inserted into the first receiving means (4) of the second bone screws (6) and may be attached thereto; and coupling means (9), whereby a first connecting element (8) and a second connecting element (5) can be connected to each other in each case, the coupling means ( 9), with a first region (10), can be detachably attached to a second bone screw (2), and in said second bone screw a terminal region (11) of a second second is retained. connecting element (5), and coupling means (9) with a second region (12) opposite the first region (10) may be connected to an end region (13) of a first connecting element ( 8). A spinal implant according to claim 1, wherein the first region (10) of the coupling means (9) is provided with a tensioning element (24) which is guided insertable into the second receiving means ( 4) and by means of tensioning means (23), which may be placed on the second receiving means (4), may be tensioned against the second connecting element (8) inserted in the second receiving means (4). The spinal implant according to claim 2, wherein the second receiving means (4) are U-shaped and are composed of two arms (17, 18), between which the support surface ( 19) for the second connecting element (8) and on which two arms (17, 18), the tensioning means (23), consisting of a locking element (25), provided with a first tensioning screw (26) , can be arranged and locked with it. A spinal implant according to claim 3, wherein the tensioning element (24) is provided with guide ribs (27, 28) which, together with guide surfaces (20, 21) provided on the arms (17 , 18), form the guides. Spinal implant according to one of claims 1 to 4, wherein the second region (12) of the coupling means (9) is configured as another tensioning means (51), to which a terminal region (13) of a first connection element (8). The spinal implant according to claim 5, wherein the other tensioning means (51) has a U-shaped receiving portion (52) for the first connecting element (8) and a threaded portion (58); opposite the U-shaped receiving portion (52) to receive a second turnbuckle (57). A spinal implant according to claim 6, wherein a clamping element (55) is inserted between the second tensioning screw (57) and the first connecting element (8) inserted into the other tensioning means ( 51). Spinal implant according to one of claims 1 to 7, wherein the tensioning element (24) and the other tensioning means (51) which form the coupling means (9) are connected to each other. in a detached way. A spinal implant according to claim 8, wherein the tensioning element (24) has at least one protrusion (49) at the nose edge, which protrudes into the other tensioning means (51). A spinal implant according to claim 9, wherein the nose-shaped protrusion (49) is provided with a threaded hole (63) into which another tensioning screw (64) can be screwed in; wherein the nose-like protrusion 49 protrudes between the second tensioning screw (57) and the first connecting element (8) of the other tensioning means (51). Spinal implant according to one of Claims 1 to 10, wherein the second connecting elements (5) have a surface structure consisting of splines (44) and grooves (43) extending from each other. substantially transverse to the longitudinal axis. Spinal implant according to claim 11, wherein the second receiving means (4) and the surface of the tensioning means (23) facing the second connecting element (5) are provided with slots ( 42) and splines (41), corresponding to the splines (44) and grooves (43) of the second connecting element (8).